CUPERTINO, CALIF. -- While Linux is not typically plagued with viruses the way some platforms are, Trend Micro nevertheless is offering its virus protection for the open source operating system.

There are only one or two known Linux viruses in the real world, according to Trend Micro, but that doesn't mean the operating system is exempt from malicious code. Linux can be used to run Simple Mail Transfer Protocol gateways that could pass infected e-mail or to run servers that can store infected files which could execute on another platform, such as Windows NT.

With that in mind, Trend Micro is now shipping its InterScan VirusWall 3.01 for Red Hat Linux, the most popular commercially available version of Linux.

Trend Micro also is offering a free tool for Red Hat and other Linux operating systems that can scan files for malicious code.

"The missing component for my SMTP gateway on Linux was being able to scan the mail," says Sam Burdic, IS manager for King Television in Seattle. "I had to have a second server in front of the Linux box just to scan mail. Now I don't have to have two servers."

VirusWall can remove viruses from inbound and outbound SMTP e-mail, including attachments, and from FTP and HTTP traffic in real time. The software also includes a Web-based update mechanism to keep virus logs current.

"The bottom line was I couldn't use Linux for e-mail," says Steve Henry, president of Executive Business Systems, a systems integrator in Chicago. "Now I can scan at the server instead of the desktop."

Henry hosts mail for a number of clients and says being able to scan at the server makes his service more valuable and attractive to users while keeping his costs down.

But the virus scanning isn't just useful for e-mail.

"There are a lot of Linux based Web-cache servers out there and now with the ability to scan for viruses within that cached data, it means you won't be retransmitting malicious code," says Chris Christiansen, an analyst with International Data Corp. in Framingham, Mass. He says the virus-scanning capabilities add to the maturation of Linux.

Other VirusWall features include centralized management with VirusWall's Web-based console for remote administration and configuration.

"As Linux begins to get closer to the mainstream, especially for use in the enterprise, antivirus software for the platform will become more useful," says Dan Schrader, vice president of new technology marketing for Trend Micro. "We're putting the support and quality assurance testing in place to meet those needs."

InterScan VirusWall 3.01 for Red Hat Linux is shipping now and starts at $725 for a 25-seat license.